Secretary of State Mike Pompeo yesterday warned Russia the United States will not "stand idly by" as Moscow inserts military personnel into Venezuela to support the regime of President Nicolas Maduro.
In a phone call with Foreign Minister Sergei Lavrov, Pompeo denounced the growing Russian military reinforcements as prolonging the political crisis in the South American country.
Pompeo told Lavrov "the United States and regional countries will not stand idly by as Russia exacerbates tensions in Venezuela," the State Department said in a statement.
"The continued insertion of Russian military personnel to support the illegitimate regime of Nicolas Maduro in Venezuela risks prolonging the suffering of the Venezuelan people who overwhelmingly support interim President Juan Guaido," he said.
Guaido is supported by the United States and most Latin American and European nations but Maduro retains the support of Russia and China, US rivals who have offered political and economic support to him.
Meanwhile, a new blackout swept across Venezuela on Monday, including much of Caracas, sowing alarm two weeks after a nationwide outage that paralyzed the country.
The power cut in the capital occurred around 1:20 pm (1720 GMT) and knocked out electricity in the city center.
After nightfall, many apartment buildings in the Caracas metro area -- home to around six million people -- were aglow again and traffic lights were back on, but people reported they were still in the dark in many other states.
President Nicolas Maduro's government blamed the previous attack on US.